Effective top-k computation with term-proximity support     

Mingjie Zhu  Shuming Shi  Mingjing Li  Ji-Rong Wen 《Information processing & management》2009

Modern web search engines are expected to return the top-k results efficiently. Although many dynamic index pruning strategies have been proposed for efficient top-k computation, most of them are prone to ignoring some especially important factors in ranking functions, such as term-proximity (the distance relationship between query terms in a document). In our recent work [Zhu, M., Shi, S., Li, M., & Wen, J. (2007). Effective top-k computation in retrieving structured documents with term-proximity support. In Proceedings of 16th CIKM conference (pp. 771–780)], we demonstrated that, when term-proximity is incorporated into ranking functions, most existing index structures and top-k strategies become quite inefficient. To solve this problem, we built the inverted index based on web page structure and proposed the query processing strategies accordingly. The experimental results indicate that the proposed index structures and query processing strategies significantly improve the top-k efficiency. In this paper, we study the possibility of adopting additional techniques to further improve top-k computation efficiency. We propose a Proximity-Probe Heuristic to make our top-k algorithms more efficient. We also test the efficiency of our approaches on various settings (linear or non-linear ranking functions, exact or approximate top-k processing, etc.).  相似文献   

国内特种文献网络数据库导览     

冯会勤 《现代情报》2008,28(2):67-69,72

文章主要介绍了国内可以检索的五类特种文献网络数据库,为广大读者和科研工作者利用特种文献提供更准确更便捷的检索途径.  相似文献   

Inter and intra-document contexts applied in polyrepresentation for best match IR     

Mette Skov  Birger Larsen  Peter Ingwersen 《Information processing & management》2008

The principle of polyrepresentation offers a theoretical framework for handling multiple contexts in information retrieval (IR). This paper presents an empirical laboratory study of polyrepresentation in restricted mode of the information space with focus on inter and intra-document features. The Cystic Fibrosis test collection indexed in the best match system InQuery constitutes the experimental setting. Overlaps between five functionally and/or cognitively different document representations are identified. Supporting the principle of polyrepresentation, results show that in general overlaps generated by three or four representations of different nature have higher precision than those generated from two representations or the single fields. This result pertains to both structured and unstructured query mode in best match retrieval, however, with the latter query mode demonstrating higher performance. The retrieval overlaps containing search keys from the bibliographic references provide the best retrieval performance and minor MeSH terms the worst. It is concluded that a highly structured query language is necessary when implementing the principle of polyrepresentation in a best match IR system because the principle is inherently Boolean. Finally a re-ranking test shows promising results when search results are re-ranked according to precision obtained in the overlaps whilst re-ranking by citations seems less useful when integrated into polyrepresentative applications.  相似文献   

图书馆文献整序职能的发展趋势   总被引：9，自引：0，他引：9  

徐荣生 《图书馆杂志》2000,19(1):1-4

根据知识创新发展需要,提出图书馆文献整序职能的三种发展趋势1、由文献整序过渡到知识整序;2、由文献固化知识整序向文献活化知识整序发展;3、由显在知识整序向潜在知识整序发展.  相似文献   

增强《文检课》教学中学生的情报意识     

王雪珍 《情报科学》1999,17(6):651-652

文章从文献检索知识的传授与情报意识的树立及高教改革的战略与情报检索意识的强化两个方面进行了论述。  相似文献   

网络环境下我国高校图书馆文献资源建设策略初探   总被引：16，自引：2，他引：14  

黄晓梅 《情报科学》1998,16(2):103-107

本文立足于我国信息网络建设的实践。探讨了网络环境下高校图书馆的文献资源建设问题,其中主要分析研究了文献采集和数据库建设这两个方面所面临的问题及其对策.  相似文献   

期刊作者的量化研究   总被引：5，自引：0，他引：5  

王崇德 《情报科学》1998,16(5):369-373,380

本文讨论了科技期刊论文作者的几个代表性的量化规律:诸如洛特卡定律以及广义洛特卡定律;普莱斯定律,加之为了使该定律达到实用目的的必要修正与改进。文章还论述了著述合作的问题,并拟合出期刊论文作者合作度的有理整函数通式。  相似文献   

我国涉农信息服务政策核心话语演变分析:以1980年以来中央“一号文件”为例     

汪汉清  樊振佳 《图书情报工作》2019,63(8):96-106

[目的/意义]对我国自1980年以来涉农信息服务政策核心话语体系构建及其演变进行研究、对话语形成的社会背景进行剖析、对话语实践进行统计与描述，以期为精准化涉农信息服务研究提供参考。[方法/过程]采用定性分析方法，运用费尔克拉夫话语分析框架，从文本向度、话语实践向度、社会实践向度三3个向度对1980以来我国涉农信息服务政策文本及其核心话语的演变进行分析，以中央一号文件为文本分析对象，对其进行话语提取、编码与归类。[结果/结论]1980年以来我国涉农信息服务可以分为两个阶段：第一阶段为1982-1986年，核心话语集中在有限的主体、对象、内容和较低的服务层次，基层基础设施建设总体发展缓慢；第二阶段为2004年至今，涉农信息服务不局限于传统的农民、农业活动以及农村地域，对象呈现多样化，服务主体规模扩大，两者界限不鲜明，服务内容呈现制度化、规模化、个性化特征，涉农信息服务服务体系逐渐形成。两阶段各有其发展特点与特色，又具有延续性和一致性、延伸性和发展性。  相似文献   

Paragraph-based representation of texts: A complex networks approach     

Henrique F. de Arruda  Vanessa Q. Marinho  Luciano da F. Costa  Diego R. Amancio 《Information processing & management》2019,56(3):479-494

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The impact of deep learning on document classification using semantically rich representations     

Zenun Kastrati  Ali Shariq Imran  Sule Yildirim Yayilgan 《Information processing & management》2019,56(5):1618-1632

This paper presents a semantically rich document representation model for automatically classifying financial documents into predefined categories utilizing deep learning. The model architecture consists of two main modules including document representation and document classification. In the first module, a document is enriched with semantics using background knowledge provided by an ontology and through the acquisition of its relevant terminology. Acquisition of terminology integrated to the ontology extends the capabilities of semantically rich document representations with an in depth-coverage of concepts, thereby capturing the whole conceptualization involved in documents. Semantically rich representations obtained from the first module will serve as input to the document classification module which aims at finding the most appropriate category for that document through deep learning. Three different deep learning networks each belonging to a different category of machine learning techniques for ontological document classification using a real-life ontology are used.Multiple simulations are carried out with various deep neural networks configurations, and our findings reveal that a three hidden layer feedforward network with 1024 neurons obtain the highest document classification performance on the INFUSE dataset. The performance in terms of F1 score is further increased by almost five percentage points to 78.10% for the same network configuration when the relevant terminology integrated to the ontology is applied to enrich document representation. Furthermore, we conducted a comparative performance evaluation using various state-of-the-art document representation approaches and classification techniques including shallow and conventional machine learning classifiers.  相似文献